Gamma-ray Bursts May Explain Fermi's Paradox

An anonymous reader writes: A new study confirms the potential hazard of nearby gamma-ray bursts. It quantifies the probability of an event near Earth, and more generally in the Milky Way and other galaxies over time: "[Evolved] life as it exists on Earth could not take place in almost any galaxy that formed earlier than about five billion years after the Big Bang." This could explain the Fermi's paradox, or why we don't see billion-year-old civilizations all around us.

Comments

Not really.

[wierd_w]

This does not really resolve fermi's paradox. It just helps define fermi's paradox.

The human race has been in mostly the same state physiologically for more than 10,000 years-- That is to say, you could clone a person who lived 10,000 years ago, and never tell them their origins, and they would integrate into our society without problem.

Our civilization has been prevented from leaving the earth by our own silliness. Our big push out of a major duldrum of ignorance has been a bittersweet one; After the renaissance, we discovered that we were capable of much more than we had. We focused on that, and coined a now much maligned term: "Progress."

For the better part of the past 2 centuries, humans were focused on attaining such "Progress", and technological advancement grew at previously unprecedented speeds. We literally went from covered wagons and horses to nuclear power in 200 years.

It wasn't biology holding humans back from this rapid achievement-- It was attitude and social conventions. Things like warring over who's god has the biggest dick, or over who has the most money. (Things we STILL fight about to this day!) When there is a major social focus to improve, we have historically demonstrated the ability to do it.

If we can thus do this-- Go from horse drawn conveyances to nuclear energy in 200 years-- then there is very little reason to expect other potential civilizations from doing so as well, and perhaps not having spent quite as much time arguing over who's god has the mightiest member.

Yet, when we look up into the sky, we dont find any. We strain with our radio telescopes, and hear only the strange EM flux of gas giants, the hissing and popping of stars, and the screams of magnetars.

This finding does not settle Fermi's paradox. It just sets a slightly smaller boundry.

Re:Not really.

[dpilot]

First, it doesn't explain Fermi's Paradox, it merely adds another term to it. In all of those various probabilities, apparently there is something like a 10% chance of not getting taken out by a gamma burst in half-a-billion years. I would also expect the odds to get better as a given galaxy "settles down", generating fewer big, hot stars and more smaller, calmer ones. Some neighborhoods are probably rougher too. I wouldn't wait around to settle Trantor, near the center of our galaxy.

Second, I wouldn't consider intergalactic contact in any serious way - the distances are bad enough for interstellar, do we really want to add a few more orders of magnitude?

Third, our presence establishes our galaxy as one of the more benign ones. There is at least one neighborhood that has been sufficiently peaceful for the last half-billion hears. Last I knew, there were no supernova candidates close enough to cause that kind of trouble any time soon, either.

Fourth, I'll focus on your word "silliness", which I think you meant as an understatement. There is conceivably a chance that we are under observation, and rank as "too silly" for any contact. The Earth has had an oxygen atmosphere for the last half-billion years, and we're on the verge of being able to detect other such atmospheres on other worlds such as Kepler has found. It's not a bad assumption that any civilization capable of interstellar travel is also better at planetary surveys than us. If they're there and within a few thousand light-years, they know something worth seeing is probably here.

At this point in physics we're stuck at the Standard Model. We have many theories that move beyond, but no facts to select among them, and many of the experiments would be incredibly expensive. But let's say one day we saw a "warp signature", it's quite possible that we could immediately discard half of those theories. (By "warp signature" I really mean physical evidence of truly advanced technology.) IF there were here watching us, and seeing our "silliness" as well as the scientific acumen of some, they would be especially careful that we see no such evidence.

Re: Not really.

[Anonymous Coward]

Total bollocks.

Nuclear propulsion could easily lift hundreds of thousands (perhaps millions) of tonnes of cargo into space, and had been demonstrated at near full scale. See NERVA and Project Orion, both of which were so technically successful that congress canceled them as to avoid having to fund true space colonization and development.

Nuclear propulsion also has the potentially to travel at relativistic speeds, potentially allowing travel to near by stars within a human lifetime.

I quote, "The reference [Orion] design was to be constructed of steel using submarine-style construction with a crew of more than 200 and a vehicle takeoff weight of several thousand tons. This low-tech single-stage reference design would reach Mars and back in four weeks from the Earth's surface (compared to 12 months for NASA's current chemically powered reference mission). The same craft could visit Saturn's moons in a seven-month mission (compared to chemically powered missions of about nine years)." (Wikipedia)

It's not my fault that politicians have decided that space propulsion should not advance significantly beyond chemical power, effectively being stupidly big and advanced firecrackers.

This is not new technology, this was developed in the 50s and 60s. Has development continued, I have no doubt that we would have industrial space stations, reasonable interplanetary travel (as in weeks/months instead of years/decades), and man would currently be planning to launch a multimillion ton expedition from the asteroid belt to nearby stars with confirmed exoplanets. The only reason we don't take advantage of space resources, and zero gravity manufacturing is because it takes $20000+ per kilo to get a payload into orbit. Drop that to $500, and everything changes dramatically.

The problems with real space exploration are speed and payload mass limitations. Nuclear energy solved both of these problems decades ago.

Re:Not really.

[ultranova]

First, us humans prefer killing each other to science. This is a proven fact.

Really? How did the arrangements for that experience go? Subject gets to choose between a test tube or a bound assistant and a (hopefully fake) knife?

Second, humanity did not go from Horses to Nukes, a very very small percent of the population did it, those geniuses have everyone else standing on their coat-tails.

A small part of the population did experiments on uranium, while the rest mined that uranium, enriched it, built the roads that carried it from the mine to the lab, etc. Accusing a tailor of riding on the coattails he made is rather absurd.

The next leap will be by a very small group that is significantly more enlightened than the rest of the 99.95% of the population. If those people are benevolent, then everyone enjoys the fruits. If they are not....... Well, things can go very differently.

The invention to trigger the next leap will be by some group that is supported by others, allowing them to focus on something besides where their next meal will come from. After it has been made, it will be turned into something actually usable by other people, manufactured by yet others, distributed by yet other people along communication and transfer infrastructure built by, you guessed it, other people...

Heroic fantasies are just that: fantasies.

WE do not glorify learning, but instead glorify morons that can carry a ball, or can sing a tune. And we Vilify in society those that do love learning and are very smart.

People respect people who can provide something useful, be it entertainment, a focus for a cultural bonding event, or a cure for cancer. If you aren't respected as much as you think you deserve, it's usually because you aren't doing anything to earn it. Merely being smart and learned is no more worthy of respect than being richr; it's what you're doing with it that earns - or doesn't - the respect.

Honestly Humanity is a joke, almost a cancer. And if an advanced civilization stumbled across us, they would probably wipe us out to make the rest of the universe safer. We as a species love to hate others, we love murder, war, and control. WE thrive on hating those that are different or think or worship different.

Humans, in general, love thinking they're better than someone else, since that's easier than self-improvement. Sometimes that manifests as merely dismissing the entire species as "riding on the coattails" of a special few ubermenschen, and sometimes the delusion reaches the point of wanting to get rid of some specific group of perceived parasites. Either way, it's bullshit.

Re: Not really.

[Anonymous Coward]

Total bollocks? :)

There's one thing nuclear propulsion cannot do, and that's exactly what you claim it can do in your opening sentence: lift that payload from the surface to orbit.
Project Orion would be using a long series of nuclear explosions to almost literally hammer the spaceship forward. You're proposing that as a LIFTOFF engine to be used within the atmosphere?

Quoting from the same wikipedia page, one of the reasons why the project was shut down:
"There were also ethical issues with launching such a vehicle within the Earth's magnetosphere: calculations showed that the fallout from each takeoff would kill between 1 and 10 people."

That's from launching within the magnetosphere, not even close to launching from the surface.

Yes, total bollocks, clearly :)

Re:Or maybe it's because

[Tablizer]

Indeed. My theory is that many of those mysterious gamma-ray bursts are civilizations earning a Galactic Darwin award.

"Hey look, we can create mini anti-black-holes in our la ~ ^ & [NO CARRIER]

Re:Simple Explanation

[Zak3056]

More simple explanation: Life is out there, it's just too far away to detect, or to visit us--and will ALWAYS be so, because you can't cheat Newton and Einstein. An alternate "simplest" explanation (though less likely) is that we are first.

To suggest that ET hasn't come to visit us because we are "too violent" or whatever, and that they are masking their presence is definitely NOT the simplest explanation--it suggests that every nearby alien species has agreed to isolate us, and every member of those civilizations is on board with the idea. No one is out there playing with an RF emitter in the VHF band, Harry Mudd hasn't stopped by and spilled the beans, no one's even accidentally done anything to give the game away.

Sorry, I'm just not buying that.

Re:WTF

[dnavid]

From TFS:

They further estimate that GRBs prevent complex life like that on Earth in 90% of the galaxies.

So, life possible on 10% of the galaxies means that those are none at all? What about our own one? This smells of clickbait.

The Fermi paradox basically states that if life on Earth is the typical result of similar conditions, the probability is far higher that there are older, more advanced civilizations, and eventually on timescales far smaller than the universe has existed we should eventually have bumped into one of them as they spread throughout the galaxy, even the universe.

The paper suggests two effects of gamma ray bursts that alter that calculation. First, a given location was more likely to be exposed to a gamma ray burst at earlier times in the universe, when the population of large hot stars was higher and overall density of the universe was higher. Therefore, its possible that even though the universe is 14 billion years old during a significant percentage of that time the universe was too dense and the frequency of gamma ray bursts too high to allow a sufficiently high technological civilization to arise. That's why there aren't any really old civilizations, or alternatively why there are so few that they tend to be very far away statistically. Second, even after the universe had expanded enough to make gamma ray bursts less likely to completely sterilize all planets everywhere its still the case that most parts of most galaxies are still too dense to avoid getting hit by them.

So its possible the reason why we have not yet seen a very old highly advanced civilization is that the actual probability of one being old enough, and close enough, for us to have bumped into (or rather for them to have bumped into us) is a lot lower than we might assume, even if the conditions to initiate life are pretty common. Nearly all of them have been wiped out before they could advance to the point of being able to colonize on an interstellar level and avoid being driven to extinction by gamma ray bursts.